Banderder - Ringerder

The earth electrode is suitable for supplementing systems with insufficient earth contact resistance. The bonding earth electrode is laid directly in the ground at a depth of at least 70 cm. It is important that the ground remains permanently moist and is not covered by surface coverings.

The length of the banderoder should be dimensioned so that sufficient earth resistance is ensured in the corresponding soil. Normally, the length is no less than 10 m and a maximum of 15 m in damp soil. To ensure maximum contact with the ground, the banderder is laid horizontally, as opposed to being set in concrete.
Corrosion-resistant materials such as copper or hot-dip galvanized steel should be used as the earth electrode material. The minimum cross-section is 50 mm² for copper and 75 mm² for steel. Earth electrodes with a rectangular cross-section must be at least 3 mm thick.

One end of the bonding earth electrode must be led out of the ground at an easily accessible point. It is advantageous to simultaneously provide the connection point with the earthing conductor as a disconnection point for control measurements.

Minimum requirements:

• Minimum cross-sections: copper 50 mm² and steel 75 mm²
• Minimum thickness for bonding earth: copper 2 mm and steel 3 mm
• Aim for an earth contact resistance of 10 Ω

Standards/regulations: SEV4022, SEV3755, NIN, grid operator guidelines

According to the SEV 4022 guidelines, the following points must be observed for ring earthing:

• The ring earth electrode is laid outside the building at a distance of at least 1 m from the building and at a depth of 0.7 m in the ground
• The ring earth electrode must be laid in the ground over at least 80% of its length and closed to form a ring.
• Missing lengths that exceed 20 % and 20 m must be compensated for. Under no circumstances may more than 20% or more than 20 m be missing.
• Conductors laid in the ground should preferably be made of copper with the minimum dimensions according to the standard.